The lipopeptide surfactin induces systemic resistance against Sclerotium rolfsii in Arachis hypogaea L.

JOHAN STIBEN RODRIGUEZ MELO; MARIA LAURA TONELLI; FERNANDO IBAÑEZ; ADRIANA FABRA

Congreso; III Conferencia Iberoamericana de Interacciones Beneficiosas Planta ? Microorganismo ? Ambiente (IBEMPA); XXVIII Reunión Latinoamericana de Rizobiología (RELAR); XVI Reunión Nacional de la Sociedad Española de Fijación de Nitrógeno (SEFIN); 2017

Induced Systemic Resistance (ISR) is a long distance signalling mechanism that provides broad spectrum and long-lasting resistance to future infections throughout the plant. Some of the bacterial compounds involved in ISR activation include flagellin, lipopolysaccharides, and several secreted or second metabolites like siderophores, volatile, phenolic compounds (Vleesschauwer & Hofte 2009, Lugtenberg & Kamilova 2009) and cyclic lipopeptides (surfactin, iturin & phenglycine) (Ongena & Jacques, 2008). ISR mechanism can be globally seen as a three-step process sequentially involved (Figure 1). First, the phenomenon is initiated by plant perception of eliciting cells or molecules produced by elicitor agents. Second, the signal transduction (via ethylene and jasmonic acid signaling pathways activation) and the establishment of priming state, which implies an accelerated activation of the defense responses after a pathogen attack. Finally, the defense mechanisms expression that limits or inhibit the future entry of pathogens into plant tissues (Mariutto & Ongena, 2016). Priming state is characterized by the memory of the stimulus, a low metabolic cost for plants, a more robust defense response and a better performance of pathogen challenged plants. In this sense, priming is postulated as a low-cost defensive and adaptive measure because defense responses, after the perception of a challenging signal, will be activated in a faster, stronger and long-lasting way (Hilker et al., 2015; Conrath et al., 2015).